Screening of Fungi for Decolorization of Dye consequence azo dyes are recalcitrant in aerobic wastewater

Screening of Fungi for Decolorization of Dye Wastewater

Merih Kıvanc + , Mine Doğruer Özen

Anadolu University, Faculty of Science,Department of Biology, Eskişehir, TURKEY

 Abstract. A total of 40 fungi were screened for their ability to decolorize Xiron orange RHD (FW), Tobactive scarlet P2R (Kimsa). Microorganisms having the ability of decolourization of organic colorants

were isolated from Porsuk stream, soil and wastewater of textile factory. Four strains of Fusarium, Penicillim

expansum, P. citreo-viride, Aspergillus flavipes, Trichoderma harzianum Paecilomyes variotii have been

chosen for this study. In addition to these strains four different strains of Myrothecium were also used in this

study. By using the those strains, maximum decolourisation was observed at 25oC pH 7.0.Among these,

maximum decolourisation was obtained by A. flavipes. It was followed by T. harzianum, Fusarium sp2.

These strains has decreased B.O.D. degree of was the wastewater of textile factory on the rates of 17.7% and

24.2%.

Keywords: texile dye, fungi, decolourization

1. Introduction

Azo compounds are used extensively in the food, pharmaceutical, cosmetic and textile industries [1].

Aromatic azo groups are not synthesized in nature, azo dyes are considered to be xenobiotics [2]. As

consequence azo dyes are recalcitrant in aerobic wastewater treatment plants. However, provided that the

proper conditions and microorganisms are used, biodegrading of azo dyes is possible [3].

Wastewater treatment systems generally do not remove the dyes, wastewaters from textile industry result

in pollution of the environment. The elimination of collared effluents in wastewater is based mainly on

physical or chemical methods. Although these methods are effective, they suffer from such shortcomings as

high cost, formation of hazardous by-products and intensive energy requirements. Therefore, as a better

alternative, microbial biodegradation methods are receiving attention. The use of white-rot fungi has

attracted increasing attention as these organisms have the ability to metabolize a diverse range of polluting

compounds. Phanerochaete chrysosporium, the most extensively studied white-rot fungus, has been shown

to metabolize and decolorize textile dyes [4], [5].

Bio-decolourization of lignin-containing pulp and paper wastewater using white rot fungi

P.chrysosporium and Tictoporia sp. Due to high oxidative potential of many of the enzymes associated with

white rot fungi, e.g. ligninase, laccase, Mn-peroxidase [6], [7]. Several other dye decolorizing fungal species

have been reported, which include Aspergillus niveus 2 ve Fusarium moniliforme [8].

It is thus not surprising those efforts to isolate from nature microorganisms utilizing azo dyes as carbon

sources where unsuccessful. However, adaptation experiments in chemostats and carefully adjusted selective

pressure let to bacterial cultures which mineralised the carboxylated azo dyes.

As for dye colour removal, review [9], [10] described the ability of Rhodococcus, Bacillus cereus and

Plasmiomonas/Achromobacter to degrade soluble dyes, acid red dye and five azo-dyes, respectively.

On the other hand, textile dyes were found strongly adsorbed and held by wastewater treatment plant

sludge that was land filled. This suggests that adsorption may play another key role in bio- decolourization.

  Corresponding author. Tel.: + 905374326098

E-mail address: mkivanc@anadolu.edu.tr

International Proceedings of Chemical, Biological and Environmental Engineering, V0l. 100 (2017)

DOI: 10.7763/IPCBEE. 2017. V100. 1

1

There is not much information about the effects of thenon-white-rot fungi on decolourization of azo dyes.

In this research, isolated fungi were used and the ability of these organisms to decolorize Xiron orange

RHD(FW),Tobactive scarlet P2R(Kimsa)tested.

2. Materials And Methods

2.1. Microorganisms Myrothecium leutricum, M.penicilloides, M.masonii obtained from Norten Research Center, USA, Peoria

IL. Fusarium sp.1, Fusarium sp2, Fusarium sp 3, Fusarium sp4, Penicillium expansum Aspergillus flavipes,

P.sitreo-viride, Tricoderma harzianum and Paesilomises variotti was isolated in our laboratory.

They were maintained through periodic transfers on sabauroud dextrose agar at +4 o C. Subculters were

made every 3 to 4 weeks.

2.2. Dyes Xiron orange RHD (FW), Tobactive scarlet P2R (Kimsa) were obtained from textile fabric, Eskişehir,

Turkey.

2.3. Wastewater A textil dye factory in Eskişehir provided the wastewater. From a textile dyeing factory,

Sample I wastewater from dyeing, pH 7.5 dark green

Sample II wastewater from dyeing, pH 7.0

Sample III wastewater from dyeing, pH 8.5 brown, flom

Sample IV wastewater from dyeing, pH 7.5 dark

Sample V wastewater from dyeing, pH 8.5 Lila

2.4. Isolation of Fungi Water samples were collected from Porsuk river in Eskişehir (Turkey) that is heavily polluted by textile

wastewater. And soil samples were collected textile fabric in Eskişehir. Nutrient agar and potato dextrose

agar petri plates supplemented with dyes (1%) used to screen soil, water and waste water samples for

colonies circlet by a clear decolorized zone. Isolates were identified by using the methods and identification

keys for fungi (Hasenekoğlu 1991).

These fungi were then tested for dye decolourization under submerged culture condition at near ambient

temperature for up to two weeks.

2.5. Decolourisation of Dyes with Fungi Cultures were cultured at 25

o C in malt extract broth. After one week of incubation, they were filtered

with Whatman no 1 filter paper then weighed.

Wet cell cake were mixed with specific aqueous dye solution (0.1%) in 1:3 weight ratio and incubated

for 1 and 2 week. OD measured after 1 and 2 week.

Decolorizing activity of Tobactive scarlet P2R. Xiron orange RHD were assayed by measurement of the

decrease in colour density at 663nm, 514nm and 490nm respectively. The decolorizing yield was expressed

as the degree of the decrease in absorbance at the same wavelength.

Each treatment was carried out in duplicate and results obtained are given as the arithmetic mean.

2.6. Effect of Dye Concentration The culture of Fusarium sp2, A.flavipes and T. harzianum was gradually exposed to increasing

concentration of dye (0.1mg/l, 1mg/l,10mg/l). Decolorizing activity of Tobactive scarlet P2R, Xiron orange

RHD were assayed by measurement of the decrease in colour density at 663nm and 514nm respectively.

2.7. Effect of pH

2

The pH of the individual culture was adjusted to 3.0, 5.0, 6.5 and 7.0 and all cultures were incubated at

25 o C.Decolorization of dyes were monitored. The absorbance was measured at 663nm and 514nm to

determine the concentration of Tobactive scarlet P2R. Xiron orange RHD.

2.8. Effect of Temperature Individual cultures were incubated at 5, 25 and 35

o C. Decolorization of Xiron orange RHD (FW)

(Orange 13), Tobactive scarlet P2R (Kimsa) (Red mix) were determined the cell free supernatant. Its

absorbance was read at OD663 Tobactive scarlet P2R OD514 Xiron orange RHD OD490.

Decolourization of textile dyes were determined as follows;

Decolorization (%)=Initial absorbance- absorbance x100

Initial absorbance

2.9. Decolorization of Dye Containing Wastewater by Fungi Real dye containing wastewater samples were added to fungi and its effectiveness in dye color removal

evaluated. They were each mixed with 5 days old mycelia in roughly 2.5:1 weight ratio and observed after 1-

2 weeks static.

3. Result And Discussion

Xiron orange RHD (FW), Tobactive scarlet P2R (Kimsa) which is monoazo dye has seen extensive in

textile dying. Fusarium sp., P.expansum, P. citreo-viride, A.flavipes, T. harzianum, P.variotii were capable

of decolorizing Xiron orange RHD (FW), Tobactive scarlet P2R (Kimsa) produced clear zones surrounding

its colonies on the agar plates. Mou et al [11] and Karaca ve Kıvanç [8] also reported similar results. Mou et

al [11] reported the decolourization activity of the Myrothecium and Ganoderma culture filtrate. Maximal

decolorizing activity of A. flavipes are within 14 days. Bio-decolourisation was evident and effective all

turned colourless to naked eyes. T. harzianum also showed high decolorizing ability for Tobactive scarlet

P2R. The Trichoderma species were degrade aromatic pollutants [12]. A. niger, F. oxysporum and

Trichoderma lignorum were degrade textile dye [13].

The effects of the initial medium pH on the decolorizing activity are shown in Table 1 and Table 2. From

these results it was determined that the best pH value for decolourization is 7.0 for fungi. This gives the

advantage that it is not necessary to adjust the initial pH of this type of dye effluent. The maximum

decolorizing activity for fungi was recorded within 2 weeks. M. masonii, M. cinctum, T. harzianum,

Fusarium sp.2 and A. flavipes had a higher